Sandboxie Plus, an open source tool that creates isolated containers on your Windows system, allows applications to run, install, write files, and modify registry entries without these changes reaching the actual operating system. Unlike a full virtual machine, Sandboxie does not boot a separate operating system and intercepts file and registry writes into a sandbox folder. This means that any malware, tracking cookies, or unwanted downloads are trapped in the sandbox. The tool is also a favorite among software developers for testing software. The core application is free to download and use for personal, non-commercial purposes and is compatible with both 32-bit versions of Windows 7, 8, and 10, with support spanning Windows 7 and 11. The full source code is available for download and a portable installer. Additional features require a "supporter certificate" to fund ongoing development.